Defeating Dumah

Pull the three stakes out of him to bring him back to life. Lure him into the furnace room very slowly -- if you move too fast, he will return to his room and you will have to begin again. Turn on the gas and hit the switch after he is in the furnace room to fry him.

Defeating Zephon

Bring a torch with you to the fight with Zephon. Run up to his belly, and swipe the torch at the hole for a bit of damage. He will attack with his leg, and get it stuck in his belly. Strike the leg. He will be heavily damaged. Strike the egg hole to cause more damage. Any time he gets a leg stuck in the ground, hit it with the torch, then hit his egg sack to quickly kill him. This is easier than the "correct" method. After defeating . him, you will gain the ability to scale walls

Defeating Malchia

To defeat the Malchia, lure him under one of the two spike gates and release them right when he is slithering under it. Repeat this on the other side of the room. After that, lure him into the center cage, quickly jump out, run to where Malchia started from, and roll the lever. This will cause the large spikes on the ceiling to come grinding down on top of him.

Defeating Rahab

You must enter the chamber in the spectral realm. Go to the top pillar where the portal is located and materialize. After a brief exchange of words, your only task is to shoot out the windows lining the room to let in the sunlight. Use the force blast-- you do not need Soul Reaver, so do not worry about taking hits. After he dies, you will acquire the swimming ability

Fun With Humans

For those of you who feel the need to unleash your wrath upon your unsuspecting human friends, go ahead and kill them with glyphs. The other humans will not acknowledge that you are responsible. Try the force, stone, and fire glyphs. You can do fun things like sailing a worshipping human against the wall, killing him, and watching as he proceeds to slide into the water only to die again.

Defeating Kain (First Time)

Simply wait for him to materialize and hit him. He will appear behind you 90% of the time. You will acquire Soul Reaver after he is defeated.

Defeating Kain (Final Time)

Wait for him to materialize and hit him. You need soul reaver to do damage. The spirit forge in the center of the arena always automatically fills your health. Simply run over to it to accomplish this. When you strike him the first time, he appears on the second tier, again usually behind you. Finally, when you hit him on the second tier, he will materialize on the third and highest tier, again usually behind you. Quickly hit him a third time to defeat him.

Use Of The Constrict Ability

First, you must have a circular area around the target. For example: Assume that the target is a Dumahim vampire (the most common in Nosgoth). Now, without using autoface, run a complete circle around the vampire until Raziel is followed by a trace of blue energy. This energy, once fully invoked, will "constrict" the vampire, causing it to be momentarily stunned -- and allowing ample time for you to finish the it off. The Constrict ability has odd effects on humans. They are as follows:

1. Certain humans, once you begin the Constrict ability, will act as though they 
plummeted into water. If you do not finish the ability, they will "drown". 

2. The human will get stunned when Constrict is half finished, allowing you to stop 
and feed on their soul. 

3. The most common and normal result is that the human will instantaneously 
die. 

The Constrict ability is required to complete the puzzle in the Chrono-chamber. Also, make sure to return to areas of Nosgoth you have already visited prior to gaining that ability. You will find that Constrict can be used on many things, and may open up useful secrets (such as Eldritch artifacts, Glyphs, and life force pieces). Constrict does not work on Kain and will not work underwater.